Note 10: Employee Benefits: 401(k) Retirement Plan Policy (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2013
Details
401(k) Retirement Plan Expense	$ 752	$ 485	$ 446
401(k) Retirement Plan Shares Held	448

Represents the 401(k) Retirement Plan Shares Held (number of shares), as of the indicated date.

No definition available.

Name:	smbc_N401KRetirementPlanSharesHeld
Namespace Prefix:	smbc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant